Method for preparing potassium carbonate

Abstract

The invention belongs to a preparation method of potassium carbonate, which relates to potassium carbonate. The invention provides the preparation method of the potassium carbonate with less process equipment, low energy consumption and no pollution discharge. The preparation method of the potassium carbonate is that: coal-fired flue gas or limekiln gas, after being washed by water, dust removed and desulfurized, is pumped in ammonia and made into (NH4)2CO3 liquid, and then Ni(OH)2 and KCl are added, NH3 is pumped in, and then Ni(NH3)6Cl2 is separated; after precipitation, K2CO3 ammonia solution is obtained and removed to a vessel, then the obtained solution is pressurized and pumped in NH3 or added with liquid ammonia, the K2CO3 ammonia solution is layered, the upper layer is supersaturated ammonia solution and the lower layer saturated K2CO3 ammonia containing solution; extraction method is adopted to obtain K2CO3 ammonia containing saturated solution; the K2CO3 ammonia containing saturated solution is heated to evaporate and filtered to remove the residue NiCO3 after being deaminated, and then evaporated to dryness, thus K2CO3 product is obtained; the Ni(NH3)6Cl2 is dissolved in water, added with lime and then heated to evaporate and deaminated thoroughly and Ni(OH)2 is filtered from Ni(NH3)6Cl2 solution to be reused, thus the filtrate is condensed to obtain CaCl2 product.

Description

technical field [0001] The present invention relates to a kind of carbonate of potassium, especially relate to a kind of preparation method of potassium carbonate. Background technique [0002] Currently, the production of potassium carbonate (K 2 CO 3 ) methods mainly include electrolysis and ion exchange resin method. Although the products prepared by the electrolysis method are of high quality and pollution-free, the equipment requirements are high, the power consumption is large, and the cost is high. Although the ion exchange resin method is simple and feasible, it consumes a lot of energy and pollutes a lot. Ionic membrane fluidized bed method has been paid attention to as a new process, but there are still some technical difficulties, and it has not been popularized yet. [0003] The invention patent application with the publication number CN1092379 provides a process and equipment for preparing potassium carbonate. The powder or grinding material in the potassium...

AI Technical Summary

Problems solved by technology

Although the products prepared by electrolysis are of high quality and pollution-free, the equipment requirements are high, the power consumption is large, and the cost is high.

Although the ion exchange resin method is simple and feasible, it consumes a lot of energy and pollutes a lot

Ionic membrane fluidized bed method has been paid attention to as a new process, but there are still some technical difficulties, and it has not been popularized yet.